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<h1 class="title">main.cpp 示例文件</h1>
<span class="subtitle">gestures/imagegestures/main.cpp</span>
<!-- $$$gestures/imagegestures/main.cpp-description -->
<div class="descr"> <a name="details"></a>
<pre class="cpp">

  <span class="comment">/****************************************************************************
  **
  ** Copyright (C) 2016 The Qt Company Ltd.
  ** Contact: https://www.qt.io/licensing/
  **
  ** This file is part of the examples of the Qt Toolkit.
  **
  ** $QT_BEGIN_LICENSE:BSD$
  ** Commercial License Usage
  ** Licensees holding valid commercial Qt licenses may use this file in
  ** accordance with the commercial license agreement provided with the
  ** Software or, alternatively, in accordance with the terms contained in
  ** a written agreement between you and The Qt Company. For licensing terms
  ** and conditions see https://www.qt.io/terms-conditions. For further
  ** information use the contact form at https://www.qt.io/contact-us.
  **
  ** BSD License Usage
  ** Alternatively, you may use this file under the terms of the BSD license
  ** as follows:
  **
  ** &quot;Redistribution and use in source and binary forms, with or without
  ** modification, are permitted provided that the following conditions are
  ** met:
  **   * Redistributions of source code must retain the above copyright
  **     notice, this list of conditions and the following disclaimer.
  **   * Redistributions in binary form must reproduce the above copyright
  **     notice, this list of conditions and the following disclaimer in
  **     the documentation and/or other materials provided with the
  **     distribution.
  **   * Neither the name of The Qt Company Ltd nor the names of its
  **     contributors may be used to endorse or promote products derived
  **     from this software without specific prior written permission.
  **
  **
  ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  ** &quot;AS IS&quot; AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.&quot;
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/</span>

  <span class="preprocessor">#include &lt;QtWidgets&gt;</span>

  <span class="preprocessor">#include &quot;mainwidget.h&quot;</span>

  <span class="keyword">static</span> <span class="type">void</span> showHelp(<span class="type"><a href="../qtcore/qcommandlineparser.html">QCommandLineParser</a></span> <span class="operator">&amp;</span>parser<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> errorMessage <span class="operator">=</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span>())
  {
      <span class="type"><a href="../qtcore/qstring.html">QString</a></span> text;
      <span class="type"><a href="../qtcore/qtextstream.html">QTextStream</a></span> str(<span class="operator">&amp;</span>text);
      str <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;&lt;html&gt;&lt;head/&gt;&lt;body&gt;&quot;</span>;
      <span class="keyword">if</span> (<span class="operator">!</span>errorMessage<span class="operator">.</span>isEmpty())
          str <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;&lt;p&gt;&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> errorMessage <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;&lt;/p&gt;&quot;</span>;
      str <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;&lt;pre&gt;&quot;</span> <span class="operator">&lt;</span><span class="operator">&lt;</span> parser<span class="operator">.</span>helpText() <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="string">&quot;&lt;/pre&gt;&lt;/body&gt;&lt;/html&gt;&quot;</span>;
      <span class="type"><a href="qmessagebox.html">QMessageBox</a></span> box(errorMessage<span class="operator">.</span>isEmpty() <span class="operator">?</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Information : <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Warning<span class="operator">,</span>
                      <span class="type"><a href="../qtgui/qguiapplication.html">QGuiApplication</a></span><span class="operator">::</span>applicationDisplayName()<span class="operator">,</span> text<span class="operator">,</span>
                      <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Ok);
      box<span class="operator">.</span>setTextInteractionFlags(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>TextBrowserInteraction);
      box<span class="operator">.</span>exec();
  }

  <span class="type">int</span> main(<span class="type">int</span> argc<span class="operator">,</span> <span class="type">char</span> <span class="operator">*</span>argv<span class="operator">[</span><span class="operator">]</span>)
  {
      <span class="type"><a href="qapplication.html">QApplication</a></span> app(argc<span class="operator">,</span> argv);
      <span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>setApplicationVersion(QT_VERSION_STR);
      <span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>setApplicationName(<span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">&quot;imagegestures&quot;</span>));
      <span class="type"><a href="../qtgui/qguiapplication.html">QGuiApplication</a></span><span class="operator">::</span>setApplicationDisplayName(<span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">&quot;Image Gestures Example&quot;</span>));

      <span class="type"><a href="../qtcore/qcommandlineparser.html">QCommandLineParser</a></span> commandLineParser;
      <span class="keyword">const</span> <span class="type"><a href="../qtcore/qcommandlineoption.html">QCommandLineOption</a></span> disablePanOption(<span class="string">&quot;no-pan&quot;</span><span class="operator">,</span> <span class="string">&quot;Disable pan gesture&quot;</span>);
      commandLineParser<span class="operator">.</span>addOption(disablePanOption);
      <span class="keyword">const</span> <span class="type"><a href="../qtcore/qcommandlineoption.html">QCommandLineOption</a></span> disablePinchOption(<span class="string">&quot;no-pinch&quot;</span><span class="operator">,</span> <span class="string">&quot;Disable pinch gesture&quot;</span>);
      commandLineParser<span class="operator">.</span>addOption(disablePinchOption);
      <span class="keyword">const</span> <span class="type"><a href="../qtcore/qcommandlineoption.html">QCommandLineOption</a></span> disableSwipeOption(<span class="string">&quot;no-swipe&quot;</span><span class="operator">,</span> <span class="string">&quot;Disable swipe gesture&quot;</span>);
      commandLineParser<span class="operator">.</span>addOption(disableSwipeOption);
      <span class="keyword">const</span> <span class="type"><a href="../qtcore/qcommandlineoption.html">QCommandLineOption</a></span> helpOption <span class="operator">=</span> commandLineParser<span class="operator">.</span>addHelpOption();
      commandLineParser<span class="operator">.</span>addPositionalArgument(<span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">&quot;Directory&quot;</span>)<span class="operator">,</span>
                                              <span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">&quot;Directory to display&quot;</span>));

      <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> description <span class="operator">=</span> <span class="type"><a href="../qtgui/qguiapplication.html">QGuiApplication</a></span><span class="operator">::</span>applicationDisplayName()
          <span class="operator">+</span> QLatin1String(<span class="string">&quot;\n\nEnable \&quot;debug\&quot; on the logging category \&quot;qt.examples.imagegestures\&quot; in order to\n&quot;</span>
                          <span class="string">&quot;in order to obtain verbose information about Qt's gesture event processing,\n&quot;</span>
                          <span class="string">&quot;for example by setting the environment variables QT_LOGGING_RULES to\n&quot;</span>
                          <span class="string">&quot;qt.examples.imagegestures.debug=true\n&quot;</span>);
      commandLineParser<span class="operator">.</span>setApplicationDescription(description);

      commandLineParser<span class="operator">.</span>process(<span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>arguments());

      <span class="type"><a href="../qtcore/qstringlist.html">QStringList</a></span> arguments <span class="operator">=</span> commandLineParser<span class="operator">.</span>positionalArguments();
      <span class="keyword">if</span> (<span class="operator">!</span>arguments<span class="operator">.</span>isEmpty() <span class="operator">&amp;</span><span class="operator">&amp;</span> <span class="operator">!</span><span class="type"><a href="../qtcore/qfileinfo.html">QFileInfo</a></span>(arguments<span class="operator">.</span>front())<span class="operator">.</span>isDir()) {
          showHelp(commandLineParser<span class="operator">,</span>
                   QLatin1Char(<span class="char">'&quot;'</span>) <span class="operator">+</span> <span class="type"><a href="../qtcore/qdir.html">QDir</a></span><span class="operator">::</span>toNativeSeparators(arguments<span class="operator">.</span>front())
                   <span class="operator">+</span> <span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">&quot;\&quot; is not a directory.&quot;</span>));
          <span class="keyword">return</span> <span class="operator">-</span><span class="number">1</span>;
      }

      <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator">&lt;</span><span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>GestureType<span class="operator">&gt;</span> gestures;
      <span class="keyword">if</span> (<span class="operator">!</span>commandLineParser<span class="operator">.</span>isSet(disablePanOption))
          gestures <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>PanGesture;
      <span class="keyword">if</span> (<span class="operator">!</span>commandLineParser<span class="operator">.</span>isSet(disablePinchOption))
          gestures <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>PinchGesture;
      <span class="keyword">if</span> (<span class="operator">!</span>commandLineParser<span class="operator">.</span>isSet(disableSwipeOption))
          gestures <span class="operator">&lt;</span><span class="operator">&lt;</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>SwipeGesture;

      MainWidget w;
      w<span class="operator">.</span>grabGestures(gestures);
      w<span class="operator">.</span>show();

      <span class="keyword">if</span> (arguments<span class="operator">.</span>isEmpty()) {
          <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstringlist.html">QStringList</a></span> picturesLocations <span class="operator">=</span> <span class="type"><a href="../qtcore/qstandardpaths.html">QStandardPaths</a></span><span class="operator">::</span>standardLocations(<span class="type"><a href="../qtcore/qstandardpaths.html">QStandardPaths</a></span><span class="operator">::</span>PicturesLocation);
          <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> directory <span class="operator">=</span>
              <span class="type"><a href="qfiledialog.html">QFileDialog</a></span><span class="operator">::</span>getExistingDirectory(<span class="operator">&amp;</span>w<span class="operator">,</span> <span class="string">&quot;Select image folder&quot;</span><span class="operator">,</span>
                                                picturesLocations<span class="operator">.</span>isEmpty() <span class="operator">?</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span>() : picturesLocations<span class="operator">.</span>front());
          <span class="keyword">if</span> (directory<span class="operator">.</span>isEmpty())
              <span class="keyword">return</span> <span class="number">0</span>;
          arguments<span class="operator">.</span>append(directory);
      }

      w<span class="operator">.</span>openDirectory(arguments<span class="operator">.</span>front());

      <span class="keyword">return</span> app<span class="operator">.</span>exec();
  }

</pre>
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<!-- @@@gestures/imagegestures/main.cpp -->
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